This problem asks you to determine which questions are associated with confounding and which questions are associated with effect modification. Briefly, here is the context: we are conducting an observational study to assess whether SIZE is associated with PRICE, accounting for ROOM, where SIZE = house size (Exposure/independent variable); PRICE = house price (Outcome/dependent variable); ROOM = number of rooms (covariable). - a or b the question is concerned with effect modification - a or b the question is concerned with confounding a. Is ROOM related to both SIZE and PRICE in a way that may be distorting the main association? b. Is the estimate of the association between SIZE and PRICE different for different levels of ROOM